How do managers pick a goal plan other than the default goal plan for a goal to be assign to?

We noticed that when a manager uses the Assign action from an active goal to assign it to someone else, that they are not able to select which goal plan it assigns to. As a result, anytime the Assign action is used the goal is added to the default goal plan. Is there a way to add a selection option for goal plans?

We thought that maybe if they selected Allow assignees to edit goal definition that the employee would be able to change the goal plan themselves, but even when the checkbox is selected the Edit Goal option is grayed out.